Romantic complexity fills and surrounds this superb Castle

Welcome to the none-too-subtly-named Mortmain family, wherein foundering patriarch James (Bill Nighy) -- for all symbolic definitions a dead writer -- has been allowing his prolonged delusions of literary grandeur to destroy his family's last shreds of hope and sober accountability. Rose, his eldest and shallowest, desperately seeks to escape his pretense and poverty by proffering herself to rich young American Simon Cotton (Henry Thomas). Simon and his brash brother Neil (Marc Blucas) abruptly claim inheritance to the dilapidated castle where the Mortmains have been watching good fortune dwindle for the twelve long years since James last wrote anything of consequence. Add in the boys' prissy mother (Sinéad Cusack) and their decidedly predatory in-law Leda (Sarah Woodward) and propriety hits the fan. The ensuing interactions are funny, sad, moving and, above all, astute, making I Capture the Castle a fabulous film. Even the cars are tasty.

Based on the first novel by late British playwright and author Dodie Smith (The Hundred and One Dalmatians), this 1930s British romance is narrated by the middle child, Cassandra (Romola Garai), whose fervid journal entries at the fresh age of seventeen allow us a perspective that's at once vulnerable and tenacious. Contending with the deceptively "prettier" Rose, her father, her stunning-if-thick stepmom Topaz (Sirens' Tara Fitzgerald) and her younger brother Thomas (Joe Sowerbutts, yes really) has made Cassandra complex indeed. As childhood gradually wafts away and she discovers mysterious new feelings for both Simon and handsome family helper Stephen (Henry Cavill), love, money, inspiration and dedication are explored with great warmth and wit. There's even a scene echoing John Belushi's peeping-tom debacle in Animal House, though this may be a coincidence.

Plaza Frontenac

Since the book was penned during the author's early years in the U.S., it stands to reason that its tale concerns a great deal of confusion and consternation regarding Yankee "new" money and English people who actually possess a modicum of taste. Naturally, the film riffs on this concept too, sort of like a jollified take on Jim Sheridan's The Field (one of the earliest Sean Bean-being-killed movies), with old and new worlds colliding over money and real estate issues. Also, even without viewing a single frame, you can discern a transatlantic cultural disparity: In England and elsewhere, this mild and totally family-appropriate movie earned a PG rating; here in the States, Tara Fitzgerald's brief, silly, harmless and completely non-sexual nudity earned the project an R. Now who's uptight?

Well, fortunately for us, all the characters here are uptight in the most enjoyable ways, delivered quite sparklingly by director Tim Fywell and screenwriter Heidi Thomas (both of the BBC's Madame Bovary). This is a story that's very seriously concerned with facial hair and society's relief at its removal; with closeted jealousy toward successful writers (as James whiles away his lonely hours with Agatha Christie); and especially with who is kissing whom, and why, and what exactly it means. Romantic relationships are deconstructed, reassembled and discarded before they even begin. Repartee rules, and producer David Parfitt has shaped a project that's less ostentatious and more subtly satisfying than his Shakespeare in Love.

Technically, I Capture the Castle is a class act all the way, gorgeously lensed by Richard Greatrex (A Knight's Tale) with elegant period makeup and hair by Lisa Westcott (The Madness of King George, From Hell). This critic has a weakness for accordion, which is handily harmonized into the energetic score by Dario Marianelli, whose work also graced winners such as Pandaemonium and I Went Down. Aces, the lot.

Of course, the pretty shell would be empty if the talent sucked, and, happily, they don't. Garai is a breath of fresh air in her first starring role (though her innocence likely won't survive the forthcoming Dirty Dancing sequel). She and Byrne even manage to survive a disconcertingly twee scene in which they inherit tatty fur coats and are mistaken for escaped circus bears. And not enough nice things can be said about Thomas; despite having debuted in that Spielberg movie about the stupid rubber puppet from space, he has matured into a nuanced and intelligent actor.

Everybody here gets delicious bits of business -- it's a hoot when standoffishly bohemian painter-model Topaz helpfully explains that her latest canvas, War and Peace, is "based on the novel" -- yet ultimately it's all about Cassandra. Given that her foibles primarily involve young love, sibling rivalry, confusing suitors and a fallen father figure, it's a shocker that Smith's book hasn't been adapted to the screen in the half-century-plus it's been around. The gala of London shopping, pagan fire rituals, cute boys meandering through ancient halls in tuxedos, razor-sharp dinner-party wit, familial retribution -- it's as if movie producers have been blind. But fortunately, the adaptation has arrived in its own good time, and it is suitably captivating.